Photographic images that allow recreation or approximation of the natural hues of a subject are conventionally captured on photographic film mounted in a camera. Camera speed films typically employ high bromide silver halide emulsions. Separate images of each of blue, green and red exposures are captured in blue, green and red recording layer units within the film. The blue recording layer unit contains chemically sensitized high bromide grains that may rely on native blue sensitivity or be sensitized to the blue region of the spectrum with one or more blue absorbing spectral sensitizing dyes. The green recording layer unit contains chemically sensitized high bromide grains that are sensitized to the green region of the spectrum with one or more green absorbing spectral sensitizing dyes. The red recording layer unit contains chemically sensitized high bromide grains that are sensitized to the red region of the spectrum with one or more red absorbing spectral sensitizing dyes. Dye-forming couplers are typically included in the layer units to allow dye images of distinguishable hue to be formed upon color processing. When the photographic film is intended for reversal processing to produce a viewable color positive image or when the photographic film is intended for use in exposing a color paper, the blue, green and red recording layer units contain couplers that form blue absorbing (yellow), green absorbing (magenta), and red absorbing (cyan) image dyes, respectively. When the dye image information is intended to be retrieved from the photographic film by digital scanning, the dye images can be of any hue, provided they are distinguishable.
The components used to construct color photographic films are disclosed in Research Disclosure, Vol. 389, September 1996, Item 38957. Research Disclosure is published by Kenneth Mason Publications, Ltd., Dudley House, 12 North St., Emsworth, Hampshire P010 7DQ, England. The following topics of Item 38957 are particularly pertinent to the present invention:
I. Emulsion grains and their preparation (most particularly the last sentence of paragraph (1) of B. Grain morphology); PA1 II. Vehicles, vehicle extenders, vehicle-like addenda and vehicle related addenda; PA1 IV. Chemical sensitization; PA1 V. Spectral sensitization and desensitization PA1 VII. Absorbing and scattering materials PA1 X. Dye image formers and modifiers (except A. silver dye bleach); PA1 XI. Layers and layer arrangements; PA1 XII. Features applicable only to color negative; PA1 XV. Supports.
A. Sensitizing dyes; PA2 A. Reflecting materials (particularly pertinent)
XIII. Features applicable only to color positive (except C. Color positives derived from color negatives);